Cuauhtemoc Estrada was gunned down Friday night trying to stop his daughter from being robbed.

Detectives are talking to witnesses and following up on several leads. CBS 2 cameras captured exclusively detectives zeroing in, on one particular home.

Detectives removed evidence bags from a house in Bellwood. A police dog lead investigators to a garage behind the home that located about a block away from the VFW hall where off duty Cook County Sheriff investigator Cuauhtemoc Estrada was gunned.

“He’s a good guy, overall family man. Just so happened that, now he is gone,” said Santos Flores, the victim’s cousin.

The father of four was at a family Christmas party he organized. He was shot while trying to stop his daughter from being robbed in the parking lot.

“All he talked about was serving people. He was one of the best investigators that we ever had,” said Cook County Sheriff Tom Dart.

After the shooting, police dogs led detectives to the house that they’ve now spent much of the morning searching. Neighbor Tanya Sanders says she’s known the family that lives in the house for years.

“There are two young males…probably 25 and 23. They go to work, come home. They seem to be good kids. I’ve watched them grow up,” said Sanders.

Detectives are also searching a wooded area behind the house and the roofs of nearby buildings, looking for the murder weapon. They even search around the post office across the street from the crime scene where a bullet appears to have hit a window.

“If you do something to somebody, especially taking a life, something you can’t give back, then you’ve marked yourself as well. What you sow, you shall reap,” said Sanders.

That was Sanders’ message for the person responsible for killing Investigator Estrada, who not only worked for the Cook County Sheriff’s Police, but was a former United States marine.